This trial was performed to evaluate the safety and tolerability of the FOLFOX4 regimen in Japanese patients with ACRC until the end of the third cycle according to the regulation of the Japanese Ministry of Health and Welfare. Thirty-nine patients received FOLFOX4 and 38 patients were evaluable for safety analysis. Thirty-four patients completed all three cycles, 18 of whom did not need dose reduction or prolongation of administration. The most frequent of grade 3/ 4 adverse events (the Common Terminology Criteria for Adverse Events v3.0) were neutropenia (42.1%), nausea (5.3%), and anorexia (5.3%). There were no treatment-related deaths. Neuro-sensory toxicity was a highly-frequent adverse event (78.9%), but no grade 3/4 neurotoxicity was seen. The FOLFOX4 regimen was acceptable to Japanese patients with ACRC in at least 3 cycles.